Kefir culture is a SCOBY: Symbiotic Colony Of Bacteria and Yeast (the tiny clusters are often called "grains," but there is no cereal grain involved). Every batch of kefir that you ferment will increase the culture, so you'll be able to make your own for as long as you like, and soon be giving your extra culture away, too! Each participant will receive their own culture and set of instructions.
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